Retrospective Criticism. 73 



Calddium pinnatifidum. The flowers of certain species of Jroideae have been 

 found to disengage heat in the course of their flowering ; and in Jameson's 

 Phil. Journ. for January, 1834, there is a statement of the degrees of heat 

 which Dr. Schultz has observed the flowers of Calddium pinnatifidum, as pro- 

 duced in a hot-house in the Berlin Botanic Garden, to evolve. The flowers 

 of a spadix blossom and decay " in the space of about twelve hours, and are in 

 their greatest perfection between 8 and 10 in the evening." Dr. Schultz did 

 not, previously to 5 o'clock, afternoon, find the flowers of a spadix evince a 

 greater temperature than that of the place in which they were kept : this was 

 6 1"2° Fahr. " At about 6 o'clock the flower, which had been previously without 

 any smell, gave out a very powerful odour, and indicated, on trial, 65" 1°; at 

 7 o'clock, 70-2°; at 8 o'clock, 74'7°; at half past 8, 76°; at 9, 78°; at 

 10 o'clock, 81°; and this last appeared to be the greatest height, since there 

 seemed to be no farther increase up to 1 1 o'clock. During the increase in 

 temperature evinced by the flowers, the disengagement of the odour likewise 

 increased. This became so powerful that the place was impregnated with an 

 ammoniacal vapour. In the morning the temperature of the flowers had fallen 

 to the temperature of the air," which, it is inferable from the absence of a 

 mention to the contrary, had remained uniform throughout the period named. 



Art. V. Retrospective Criticism. 



Corrections. — In IX. 672. line 2. for " salicifolia," read " salicariaefolia." 



Corrections to the Encyclopedia of Gardening, new edition. — The only cor- 

 rections which we have yet (December 20.) received are the following, by 

 the much esteemed and venerable President of the Horticultural Society, who 

 may be truly called the father of scientific gardening in England. We esteem 

 it an honour to ourselves, and a great advantage to our readers, that our 

 Encyclopaedia has received corrections from such a quarter : we are sincerely 

 grateful for them, and ardently hope that they will be continued by the same 

 excellent authority as the work proceeds. Mr. Knight's corrections to Part I. 

 are as follows : — 



§ 9. and § 46. There is no direct mention whatever, I think, in the older 

 of the Homeric poems [the Iliad] of gardens ; but the vine and the fig were 

 then raised, and, I conclude, cultivated in enclosures; for wild animals and 

 birds must have been vastly more numerous in those days than in our own. 

 There are parts in that poem which prove that the author, and probably his 

 countrymen, had not been wholly inattentive to the vegetable kingdom. One 

 of these only I shall now mention. Homer applies the epithet " seed- 

 destroying " to an aquatic tree thrown down by the Scamander. I think there 

 can be no doubt of its being a male poplar or male willow. As malleable 

 iron was wholly unknown at the period when the older Homeric poem was 

 composed, and as it appears to have been well known when the Bible was 

 written (I mean the earlier parts of it), there appears much probability of 

 the Iliad being the older. 



§ 12. The common gardener will here suppose our sycamore to be meant, 

 and not the fig mulberry, .Ficus *Syc6morus L. 



§ 14. The peach tree was not introduced into Egypt till long after the 

 Augustan age. The " Persaea " of Pliny (the tree alluded to in your para- 

 graph) was a totally different species of fruit ; and none now exists which 

 corresponds with Pliny's description. The edible part of the fruit described 

 by Pliny appears, I think (I speak from memory only), to be enclosed in a 

 kind of shell; and he speaks of its excessive sweetness, "praedulcis suavitas." 



§ 15. Irrigation is, I think, mentioned in the Iliad. A peasant is described 

 conducting a rill of water to irrigate his ground, or garden, which I suppose it 

 to have probably been. 



§ 88. I pointed out to Sir Joseph Banks, as he has stated, the lines in 



